Abstract: A purification process of an aliphatic polyester prepared in the presence of a catalyst from a hydroxycarboxylic acid or a cyclic ester of a hydroxycarboxylic acid, or a combination of an aliphatic polyhydric alcohol with an aliphatic polybasic acid, or a mixture of these compounds, comprising deactivating the catalyst while maintaining the aliphatic polyester in a molten or dissolved state, or insolubilizing and separating the catalyst and successively removing low molecular compounds. The process can provide aliphatic polyester which has a low content of unreacted monomers and low molecular weight compounds and is excellent in heat resistance and weatherability.

Abstract: A ceiling material for vehicles, said ceiling material comprises:a core material (11) composed of a resin foamed article;a protective layer (12) comprising a thermoplastic resin blended with fibers in a range of not less than 40% and not more than 80% in volume content;said protective layer (12) being provided on at least one surface of the core material (11);and a thin sheet-shaped surface material (14) provided on the surface of the protective layer (12).

Abstract: A measuring tool for collecting down hole information, which essentially has a sensor sub including plural data collecting sensors secured at a forward portion of a drilling pipe and a sonde movable in the drilling pipe. Both the sensor sub and sonde employ a set of loop antennas to effect radiocommunication between them to thereby certainly send data detected by means of the sensors to the sonde.

Abstract: There is provided a cycloolefin polymer composition comprising 8 to 40% by weight of a cycloolefin polymer [A] and 92 to 60% by weight of a cycloolefin polymer [B], both having specific properties, wherein a difference .DELTA.n.sub.D =.vertline.n.sub.D (A)-n.sub.D (B).vertline. between the refractive index n.sub.D (A) of the polymer [A] and the refractive index n.sub.D (B) of the polymer [B] is not more than 0.015. This composition is excellent in impact resistance, transparency and heat resistance, and has a good balance of these properties.There is also provided a cycloolefin copolymer composition comprising 8 to 40% by weight of a cycloolefin elastomer component [Aa] of an .alpha.-olefin, a specific cycloolefin and a non-conjugated diene which contains a polymerizable carbon-carbon double bond; and 92 to 60% by weight of a cycloolefin copolymer component [Ba] which is obtained by copolymerizing an .alpha.

Abstract: A polyimide resin composition substantially comprising 1 99.9.about.50 parts by weight of polyimide having recurring structural units of the formula ##STR1## and 2 0.1.about.50 parts by weight of a polyimide which improved melt flowability and is prepared by using 1,3-bis(3-aminophenoxy)benzene or 6,6'-bis(3-aminophenoxy)-3,3,3',3'-tetramethyl-1,1'-spirobiindane as essential diamine component, or polyether pyridine having recurring structural units of the formula: ##STR2## is disclosed. Further, a polyimide based resin composition comprising the polyimide resin composition or a polyimide copolymer obtained by using the above diamines and a fibrous reinforcement is disclosed. These compositions have remarkably good processability, excellent heat stability and repeated fatigue characteristics.

Abstract: A catalyst for cleaning exhaust gas comprises a carrier and a coated layer applied onto the surface of the carrier which comprises an aluminum oxide, a cerium oxide, a zirconium oxide, a nickel oxide, an alkaline earth metal oxide and a noble metal catalytic component. The catalyst can be prepared according to a method which comprises the steps of coating the surface of a carrier with a slurry which comprises active alumina, a cerium compound, a zirconium compound and a nickel compound, drying the coated carrier and then calcining it to complete the carrier, then impregnating the carrier with a solution comprising a catalyst component of a noble metal, drying, then immersing it in a solution of an alkaline earth metal compound, drying the immersed carrier and then calcining the carrier. The catalyst for exhaust gas-cleanup is highly sensitive to HC and CO around the theoretical mixing ratio and within the rich-region and is excellent in durability.

Abstract: An optical information recording medium is here disclosed which comprises a transparent substrate, a recording layer comprising an organic dyestuff on which information can be written by a laser beam, a reflective layer and a protective layer formed in this order on the substrate, the aforesaid optical information recording medium being characterized by containing a pit.edge control agent for the formation of recording pits, particularly a dyestuff thermal decomposition accelerator in the recording layer. By the addition of the pit.edge control agent, deviation properties and jitter properties can be remarkably improved, whereby a CD-R medium having a low error rate and good recording properties can be provided. In consequence, stable compatibility with a commercial CD player can be secured.

Abstract: Melamine cyanurate is prepared by heating melamine powder and cyanuric acid powder at 250.degree. to 500.degree. C. substantially in the absence of any liquid medium. The melamine cyanurate can be obtained in a granular form when the heating is conducted subsequent to granulation of a mixture of both the powders.

Abstract: A transparent panel heater which can be used for heating a window portion of liquid crystal displays, refrigerated showcases, freezed showcases, defrosters of windshields, and the like. The panel heater has a transparent substrate, a transparent conductive film formed on the substrate, a substantially light-transmittable metallic electrode-underling-layer formed on the transparent conductive film and a pair of metallic electrodes which are provided for electrifying the conductive film and formed on the electrode-underlying-layer. The transparent conductive film is a laminate of at least one transparent thin layer made of a nitride and/or a carbide and at least one substantially light-transmittable metallic layer. The transparent conductive film and electrode-underlying-layer are preferably formed by a dry process, and the electrodes are preferably formed by a wet plating method.

Abstract: Articles which can be degraded and disappear in the natural environment are a degradable adhesive film which can be used for surface protection or indication after printing on the film surface and has an adhesive layer on one side of a substrate film obtained from a lactic acid base polymer such as polylactic acid and a lactic acid/hydroxycarboxylic acid copolymer having a molecular weight of 30,000-500,000, and a degradable resin composition which is excellent in weatherability and comprises 100 parts by weight of a lactic acid base polymer and 0.001-5 parts by weight of one or more additives selected from ultraviolet absorbers and light stabilizers.

Abstract: A hydraulic cement composition comprising as an effective component a water-soluble amphoteric polymer obtained by Hofmann degradation reaction of an .alpha.,.beta.-unsaturated carbonamide polymer or a copolymer of .alpha.,.beta.-unsaturated carbonamide and an anionic monomer having a weight average molecular weight of 1,000-1,000,000.The primary amino group produced as a result of the Hofmann degradation reaction provides excellent cement dispersing capabilities.

Abstract: A formed thermoplastic resin article is made of a thermoplastic resin and a foamed elastic polymer finely dispersed in the thermoplastic resin. The formed thermoplastic resin article can be produced by blending an elastic polymer, in which an endothermic foaming agent decomposable at a temperature of at least 160.degree. C. was mixed in advance at a temperature lower than a decomposition temperature of the endothermic foaming agent, in a thermoplastic resin and then plasticizing and forming the resultant resin blend at a temperature at least equal to the decomposition temperature of the endothermic foaming agent.

Abstract: An optical recording medium comprises a substrate, a recording layer overlying the substrate in a manner such that it is not present at the inner and outer peripheral portions of the substrate, a metal reflective layer overlying the recording layer in a manner such that the inner periphery of the metal reflective layer is coterminous with that of the recording layer while the outer peripheral portion of the reflective layer extends over the outer perphery of the recording layer, and a protective layer wholly covering the metal reflective layer extending over the recording layer, both at the inner and outer peripheral portions. The optical recording medium exhibits an excellent adhesion strength of the protective layer even when stood under high humidity and high temperature conditions for a long period of time, and the protective layer is not peeled off when subjected to a tape peeling test.

Abstract: The present invention relates to an amorphous polyimide or a polyimide copolymer having a requisite structural unit consisting of one or more recurring structural units represented by the formula (1): ##STR1## wherein X is a direct bond, oxygen atom or sulfur atom, and R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are individually a hydrogen atom or methyl, and Ar is a tetravalent radical having 6 to 27 carbon atoms and being selected from the group consisting of a monoaromatic radical, condensed polyaromatic radical and noncondensed polyaromatic radical having aromatic radicals connected to each other with a direct bond or a bridge member.Polyimide and the polyimide copolymer of the invention has excellent heat resistance, is outstanding in melt-flow stability, has greatly improved processability, and can be applied to structural materials, and electric- electronic appliances.

Abstract: In the process for preparing polysuccinimide by dehydration condensation of aspartic acid in an organic solvent, polysuccinimide can be obtained simply and suitably in industry by removing a portion or more of the organic solvent from the reaction mixture while charging to the reaction mixture an additional organic solvent containing less amount of water than that of the removed organic solvent.

Abstract: Disclosed is an aromatic diamine compound represented by the formula (I) ##STR1## wherein R is H or CH.sub.3. Also disclosed is a bismaleimide compound represented by the formula (IV) ##STR2## wherein R is H or CH.sub.3, A resin forming composition comprising these compounds is also disclosed. The compounds are useful as raw materials for resins, and the resin forming composition and the resin can provide excellent heat resistance and impact resistance and low hygroscopicity.

Abstract: A photo-setting resin composition is here disclosed which comprises a photo-setting resin precursor and a dyestuff for uniformly coloring the photo-cured resin; and there is also disclosed a method for preparing a color filter by the use of this photo-setting resin composition.

Abstract: A 2H-1-benzopyran-2-on compound represented by the formula (1): ##STR1## and a colorless ultraviolet absorber consisting of the compound, and a thermoplastic resin composition and formed article comprising said ultraviolet absorber. The compound can provide a thermoplastic resin composition and a formed article of the composition having excellent heat stability and sublimation resistance, comprise a non-coloring ultraviolet absorber, and are excellent in ultraviolet barrier property.

Abstract: A printed circuit inner-layer copper foil having inverted tear drop-shaped fine nodules formed on both surfaces of a copper foil each having surface roughness Rz=1 to 3 .mu.m, the nodules having a length of 0.6 to 1.0 .mu.m and a maximum diameter of 0.2 to 0.8 .mu.m, and a process for producing said inner-layer copper foil.

Abstract: Provided by the present invention are novel diguanamine derivatives, led by 2,5/2,6-bis(4,6-diamino-1,3,5-triazin-2-yl)-bicyclo[2.2.1]heptanes and 1,3/1,4-bis(4,6-diamino-1,3,5-triazin-2-yl)-cyclohexanes, and derivatives thereof, applications of these compounds in fields such as adhesives and paints, utilization of these compounds in flame-retarding, thermal stabilization and compatibilization methods of resins, thermosetting molding compositions and thermosetting expansion-molding compositions making use of these compounds, as well as polymeric microspheres also using these compounds. These compounds are expected to find wide spread industrial utility as various excellent properties can be obtained by using them.